Noiseless typewriter action



Feb. 27, 1934; R. ATTI NOISELESS TYPEWRITER ACTION 7 Fild Aug. 21, 1950 INVENTOR; 'fim /nqzz 47-77 7 BY M ATTORNEY Patented Feb. 27, 1934 NOISELESS mnwarrnn sorrow Raphael Atti, Union City, N. 1., assignor, by mesne assignments, to L C Smith at Corona Typewriters Inc-,New York, N. Y.. a corporation of New York Application August 21, 1930. Serial No. 476,817

12 Claims. (01. 197-27) This invention relates to typewriters in general and more especially to actions for producingsocalled noiseless typewriters. A

Amongst the objects of the present invention,

it is aimed to provide an improved noiseless type-' writer action, containing a minimum number of parts which can be produced at a comparatively low cost.

- f Specifically it.is an object of the present invention to' provide a noiseless typewriter action which relies upon a pivotally mounted spring controlled cam to guide the type bar into printmg position where its maximum print forming pressure will be free to be exercised and the noise 1!! creating impact blow practically absorbed.- 7 These and other features, capabilities and advantages of the invention will appear from the .subjoined detail description of one specific embodiment thereof illustrated in the accompanying drawing in which Figure 1 is a side-elevation showing one unit of a typewriter action in non-printing position with the typewriter frame diagrammatically illustrated;

Fig. 2 is a similar side elevation showing said unit in printing position with the typewriter frame diagrammatically illustrated:

In the embodiment illustrated, there is shown a writer frame 1 in dotted lines having 1 above the same, the typewriter platen 2, by suitable means not shown. Below the platen 2 in the present instance, there is shown a felt cushion 3, preferably mounted on the frame it. To the front of the frame 1 in the present instance, there is provided another felt cushion 4.

In the drawing, a single unit of a typewriter action is illustrated but it is of course obvious that this action can be duplicated at random according to the number of type characters to be used. The unit of type bar action here illustrated consists essentially of a key bar 5 having a key 6 at its front free end and pivotally mounted on the shaft 7 journaled in the frame 1.

The key bar 5 in the present instance is bent at 8 to clear the shaft 9 of the lever 10 which is provided with a bifurcated projection 11 to receive the pin 12 on the key bar 5. The upper end of the lever 10 is provided with a pin 13 travelling. in the slot 14 formed at the rear end of the type bar 15 which is provided with type 16 at its front end and at its rear end pivotally mounted on the shaft 1'! glournaled in the frame 1.

In its non-printing position as shown in,Fig.

iii 1 the type bar 15 rests on the cushion 4.

For guiding the type bar 15 and therewith the type bar action into printing position to eliminate the noise creating impact blow without diminishing any of the print creating pressure, the cam lever 18 is provided. It is pivoted on the shaft 19 formed on the frame 1 and provided with the cam face 20 throughout its length which is maintained in contact with the upper face 21 of the type bar 15 throughout the movement of said type bar 15 by the spring 22, one end 55. of which is secured to the shaft 19 and the other end to the abutment 23 formed on the frame 1.

In operation, when the key 6 is engaged and depressed it will rock the key bar 5 about the shaft 7 to depress the pin 12 in turn to rock the lever 10 to actuate the type bar 15 to swing upward into the position shown in Fig. 2 Throughout its upwardly swinging action, the face 21 of the type bar 15 will be engaged bythe cam face 20 of the cam lever 18 to control its movement 76 and thus iron out or absorb the noise creating impact blow. Due to the momentum of the upwardly swinging type bar 15 and similarly of the cam lever 18, the lever 18 will swing over the cause its nose 24 to strike the cushion 3, while the type 80 16 will engage the paper or other printing surface formed on the platen 2.

When the key bar is released the type bar 15 will return under the urge of the spring 22 to strike the cushion 4 in its position of rest as indicated in Fig. 1. In this action it will be noted, the spring 22 not only co-operates with the cam lever 18 to iron out the noise creating impact blow but will also function to return the action to normal position, thus dispensing with the returning spring or the like heretofore necessary, especially with this type of action.

It is obvious that the device for dissipating the noise creating impact blow may be associated with any other typewriter action without departing from the general spirit of the invention, and that various changes and modifications may be made to the details of the invention without departing from the general spirit of the invention as set forth in the appended claims.

I claim:

1. In a typewriter action, the combination with a key bar, of a type bar operatively connected to said key bar, a noise dissipating device including a cam lever maintained in engagement with said type bar, and a spring co-operating with said lever to increase the reactive force of said lever, during, and in opposition to, the movement of the type bar into printing position to effect substantially uniform velocity of the type bar when actuated into printing position.

2. The combination with a frame, of a platen above said frame, a key bar pivotally connected to said frame, a type bar having a cam engaging face and pivotally connected to said frame, a lever operatively connected to said frame and having a cam face, and a spring for maintaining the cam face of said cam lever in engagement with the cam engaging face of said type bar to guide the type bar into and out of printing position.-

3. The combination with a frame, of aplaten above said frame, a key bar pivotally connected to said frame, a type bar having a cam engaging face and pivotally connected to said frame, a lever operatively connected to said frame and having a cam face, a spring for maintaining the cam face of said cam lever in engagement with the cam engaging face of said type bar to guide the type bar into and out of printing position, and a cushion for supporting the type bar in non-printing position and for receiving the same on its return from printing position.

4. The combination with a frame, of a platen above said frame, a key bar pivotally connected to said frame, a type bar having a cam engaging face and pivotally connected to said frame, a lever operatively connected to said frame and having a cam face, a spring for maintaining the cam face of said cam lever in engagement with the cam engaging face of said type bar to guide the type bar into and out of printing position, and a cushion for receiving the end of the cam lever at the end of the printing action.

5. In a typewriting machine, the combination of a type carrier, means for actuating said carrier, a platen withwhich said carrier is coactive to make a typeimpression when the carrier is actuated by said actuating means, and means interposed in the path of printing movement of the carrier to limit printing movement of the carrier without impact between the carrier and said limiting means.

6. A typewriting machine having a platen, a pivoted type bar carrying type adjacent oneend thereof coactive with the platen to-print, means for swinging the type bar on its printing strokes, and means coactive with the type bar between the bar pivot and the type as the type bar swings to printing position to first retard and then limit the printing stroke of the bar without impact between the bar and said retarding and limiting means.

7. A typewriting machine having a pivoted type bar carrying type adjacent oneend thereof, a platen, means for swinging the type bar into printing relation with the platen, and a cam pivoted to swing in the path of printing movement of a portion of the type bar that is located be-' tween the bar pivot and the type and correlated with said portion of the bar to constantly engage the leading edge of said bar portion throughout the printing strokes of the bar.

8. A typewriting machine as claimed in claim 7, in which said cam consists of a single arm pivoted at one end and having a cam edge which is engaged with said leading edge of said bar portion and extends to the pivoted end of the said arm, along which cam edge the point of contact of the leading edge of the bar portion with the cam arm travels to the pivoted end of the cam arm during the printing strokes of the type bar;

9. In a visible writing typewriting machine, the combination of a platen, a type bar pivotally supported to swing upwardly and rearwardly to the platen to print, means for swinging the type bar to the platen, and an impression controlling arm pivotally supported to swing upwardly and rearwardly in the path of printing movement of said type bar, said arm normally making an angle with said bar and having its under edge engaged adjacent its free end with the upper edge of the bar forward of the bar pivot, and the pivotal axes of the bar and arm being positioned for progressive travel of the point of contact between the bar and arm to the pivoted end of the arm during the printing strokes of the bar.

10. A typewriting machine as claimed in claim 9, in which the arm and type bar are constantly held in contact by a spring.

11. In a typewriting machine, a printing couple comprising a normally stationary and forwardly extending type bar pivotally supported adjacent its rear end, a platen above and to the rear of the forward end of the type bar, means for swinging the type bar upward and rearward to the 1 ov platen, an impression governor pivotally supported above the type bar to swing in one direction about an axisparallel with the type bar axis under thrust of the typebar thereagainst to absorb type bar momentum during upward and rearward swinging movement of the type bar, said governor having abar-thrust-r'eceiving surface adapted for progressive travel of the point of application of bar thrust thereto toward the axis of the governor as the type bar approaches the platen, and said governor being positioned relatively to the bar to insure contact between the bar and said thrust-receiving surface of the governor at the end of the upward and rearward swinging movement of the bar. 5

- 12. In a visible writing typewriting machine having a printing couple comprising a platen and a front strike type bar pivotally supported to swing rearwardly to the front portion of the platen, the combination with said printing cou- 13o ple of an impression governor located below the printing point and pivotally supported for swinging thereof by a portion of said type bar during rearward swinging of the bar without impact between the bar and governor.

RAPHAEL A'II'I. 

